1. Field of the Invention
This invention relates to the preservation of an oxygen sensitive liquid in a container and, more particularly, to novel and highly-effective apparatus for retarding oxidation of a liquid such as wine that only partly fills a container such as a bottle that is formed with an opening through which the liquid can be poured.
2. Description of the Prior Art
Many liquids, such as table wines, are susceptible to oxidation and must be protected against excessive oxidation. When a bottle of table wine is opened and only partly consumed, the unconsumed portion deteriorates rapidly, even if the bottle is recorked, because of oxidation by the oxygen in the air that replaces the consumed portion of the wine.
In the making of table wines, following fermentation of the grapes, a period of slow development begins which can be accomplished in a few weeks or can occupy decades, depending on the needs of the wines themselves. The action of oxygen, a twenty percent component of air, plays an indispensable role in the maturing of the wine, but exposure of the wine to oxygen must be carefully controlled.
As the newly fermented wine is transferred to casks, and later from casks to bottles, it is exposed to air, absorbing some oxygen. In cask, rather liberal access of air to the wine induces a period of rapid development. If left too long in cask, the wine quickly grows old, losing its desirable qualities even before it matures. Only slow maturing in bottles, following a short time in cask, can allow complex wine, particularly red wine, to develop the subtle qualities for which it is valued.
Until the eighteenth century, no means was known to control the maturing of wine. Wines were stored in barrels, and were consumed promptly in a race against spoilage. Only with the invention of the bottle cork and corkscrew did the art of winemaking begin to acquire refinement. The cork allowed the vintner to control for the first time the exposure of table wine to the oxygen of the air.
Even after bottling, wine continues slowly to absorb minute amounts of oxygen, which enters the bottle very gradually through the cellular structure of the cork and through the space between cork and glass. Although fatal in large doses, oxygen in controlled amounts is instrumental to the growth and maturation of wine.
Ordinarily the cork is drawn from a bottle of table wine with the intention of drinking the contents without delay--e.g., within the span of a meal. It is common knowledge that free exposure of wine to the air causes the wine to oxidize and age rapidly--within a few hours at most. The excessively oxidized wine may still be drunk, but with diminished pleasure. It will have lost its freshness and subtlety, and taken on a flat, lifeless and bitter taste.
Several conventional means are available to preserve the character of the remaining wine in a bottle that has been opened; all have serious drawbacks, especially when used in the home. One way is to drop sanitized glass marbles into the bottle until enough marbles have piled up in the bottom to displace the wine upward to the level of the bottle's neck. The cork may then be replaced, and the wine will be protected from the air. This method has the advantage of simplicity and economy. However, it is time consuming and inconvenient. The marbles are arduous to clean and insert, and the wine in the marble-filled bottle is hard to pour. This method is worth the trouble only for a rather fine or expensive wine.
Another means, of recent invention, is a nitrogen-atmosphere device marketed under the name "Cruvinet." The device is made in various models for use in the home and in clubs, bars and restaurants. Different models can accommodate different numbers of bottles at one time. The smallest model, intended for home use, can accommodate a single bottle, while the largest device developed so far, intended for commercial use, can accommodate ninety-six bottles. The device enjoys a certain success among commercial establishments, but it has very serious drawbacks in the home.
The device replaces wine drawn from a bottle with nitrogen gas, which is inert and has no effect on the remaining wine. The nitrogen prevents oxygen from reaching the wine, thereby protecting it from rapid oxidation. The disadvantages of the device for home use lie in its size, inconvenience and cost. The smallest model, which holds one bottle, costs several hundred dollars. It takes up considerable space, in part because it must house a tank of nitrogen gas, without which it cannot function. The device therefore takes on the role of a piece of furniture, with its associated problems of decor and appropriateness. The nitrogen gas must be continually replenished, an additional expense and inconvenience. Furthermore, the tubes and fittings used to draw off the wine from the bottles must be dismantled and cleaned after each use, a cost in time and effort. The device is acceptable in commercial use; in the home its use is limited to those among the well-to-do who can accept its obtrusiveness and need for maintenance.